1. Field of the Invention
The present invention relates to a guide roller unit for guiding the conveyance of a sheet, a guiding device and an image forming apparatus provided with the same.
2. Description of the Related Art
An image forming apparatus such as a copier or a printer is provided with a sheet conveyance path for conveying a sheet to which an image is transferred. A guide roller unit for guiding the conveyance of a sheet is arranged in such a sheet conveyance path. A known guide roller unit has a simple construction in which a guide roller is rotatably supported by a holder formed by bending a steel plate.
Japanese Unexamined Patent Publication No. H10-198207 (D1) discloses a guide roller unit comprising a holder including a base part and a pair of bearing parts opposed to each other is formed by bending a steel plate having spring elasticity into U-shape, and a guide roller rotatably supported by the pair of bearing parts. Upon mounting the guide roller on the bearing parts, the leading end of the bearing parts are elastically widened apart and the opposite ends of a rotary shaft of the guide roller are fitted into through holes formed in the respective bearing parts from the inside. Thereafter, the bearing parts are restored to sandwich the guide roller by the bearing parts from the opposite sides, whereby the guide roller is rotatably supported. The guide roller unit assembled in this way is mounted on a mount surface of a specified mounting member. The guide roller unit disclosed in D1 publication has advantages of having a simple construction and being quite easy to assemble the guide roller into the holder.
However, the advantage of being easy to assemble the guide roller into the holder leads to a disadvantage that the guide roller is likely to come off after the assembling. How to solve this disadvantage is not particularly mentioned in D1 publication.